Installation and Servicing Instructions R 28 HE system Wall mounted condensing boiler for central heating 6 720 610 577-01.10 6 720 611 443 GB (03.
Contents Contents Safety precautions 3 6.1.3 6.2 6.2.1 6.2.2 6.2.3 Symbols 3 6.2.4 1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Details of the appliance EC Declaration of Conformity Standard package Description of appliance Accessories Casing dimensions Layout of appliance Function (with optional extra motorised valve) Electrical wiring diagram Technical data 2 Installation regulations 10 3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.8.1 3.8.2 3.8.
Safety precautions Safety precautions If you smell gas B Turn off gas service cock at the meter. B Open windows and doors. B Do not operate any electrical switches. B Extinguish any naked flames. B Telephone your gas company. If you smell fumes from the appliance B Switch off appliance (see page 24). B Open windows and doors.
Details of the appliance 1 1.1 Details of the appliance 1.3 EC Declaration of Conformity • Wall-mounted appliance, siting not dependent on room size This appliance is in accordance with the applicable requirements of the Gas Appliance Directive, Boiler Efficiency Directive, Electromagnetic Compatibility Directive and the Low Voltage Directive.
Details of the appliance 1.4 Accessories • Standard horizontal flue kit at 100 mm outside diameter for flues up to 4 m in length. • Flue duct kits for horizontal (125 mm outside diameter) for flue lengths up to 13 m and vertical flue systems for flue lengths up to 13.7 m. Fitting instructions are sent with these kits. • Heating programmers • Timer • Motorised valve is available as an optional extra.
Details of the appliance 1.6 Layout of appliance 120 221.1 221.2 27 226 20 102 32.1 29 36 271 6 415 43 9 63 416 358 18 64 423 7 18.1 418 15 8.1 295 4 417 6 720 610 599 - 00.TD Fig. 2 4 6 7 8.1 9 15 18 18.1 20 27 29 32.1 36 43 63 64 102 120 221.
Details of the appliance 1.7 Function (with optional extra motorised valve) Fig. 3 4 6 7 8.1 9 13 15 18 20 26 27 29 29.1 30 32 33 35 36 43 45 47 52 52.
Details of the appliance 1.8 Electrical wiring diagram o - orange bl - black r - red 33 365 364 61 366 363 367 ECO 4.1 25 V 153 30V/AC 230 V 310 136 135 2 312 328 302 313 151 318 124 789 L N Ns Ls LR 161 p p 300 314 p 84 M 328.1 9 M 6 M r r mains supply 18 o 226 52 52.1 56 o bl bl bl bl 36 32 6 720 610 601-02.2O Fig. 4 4.1 6 9 18 32 33 36 52 52.1 56 61 84 135 136 151 153 161 226 300 302 310 312 313 314 318 328 328.
Details of the appliance 1.9 Technical data Units Natural gas Propane Max. rated heat output net 40/30°C central heating Max. rated heat output net 50/30°C central heating Max. rated heat output net 80/60°C central heating kW kW kW 29.3 29.0 27.4 29.3 29.0 27.4 Max. rated heat input net kW 27.7 27.7 Min. rated heat output net 40/30°C Min. rated heat output net 50/30°C Min. rated heat output net 80/60°C kW kW kW 8.4 8.3 7.4 11.6 11.4 10.5 Min. rated heat input net kW 7.6 10.
Installation regulations Gas supply Condensate analysis, mg/l Ammonium 1.2 ≤ 0.01 Lead Nickel 0.15 ≤ 0.0001 Mercury Cadmium ≤ 0.001 Sulphate Chromium ≤ 0.005 Zinc ≤ 0.015 Tin ≤ 0.01 Halogenated hydrocarbons ≤ 0.002 Hydrocarbons 0.015 Vanadium Copper 0.028 pH-value 1 Total length of gas supply pipe (metres) 3 9 Gas discharge rate (m3/h) 8.7 5.8 4.6 22 18.0 12.0 9.4 28 ≤ 0.001 4.
Installation 3 Installation B Always turn off the gas cock before carrying out any work on components which carry gas. i 3.1 Fixing of the appliance, gas and flue connections, commissioning of the system and electrical connections may only be carried out by competent persons authorised by CORGI. Important remarks B Appliance should only be installed in sealed central heating systems. 3.
Installation LV RV INDIRECT CYLINDER LV RV LV RV Radiator Valve - Flow RV Lockshield Valve - Return LV Heating Return APPLIANCE LV Refer to Appliance Water Flow Diagram Safety Discharge 6 720 610 601-04.
Installation LV RV INDIRECT CYLINDER LV Radiator Valve - Flow RV Lockshield Valve - Return LV CH Zone Valve Refer to Appliance Water Flow Diagram Safety Discharge DHW Zone Valve Mains Cold Water BS Stop Valve Fixed Cylinder Type 6 720 610 601-06.1O RV Heating Return LV Hot Water Flow APPLIANCE LV RV Fig.
Installation 3.4 Wall mounting frame assembly B Take the wall mounting frame out of the package and screw together with 6 screws as shown in fig. 9. Use the inner lugs on the top and bottom horizontal sections. B Screw the pre-plumbing manifold with two screws to the wall mounting frame. 6 720 610 576-11.1O Fig. 11 6 720 610 576-04.1O 3.5 Pre-piping the system Fig. 9 200 B Hold the wall-mounting frame against the wall ensuring that it is vertical.
Installation Condensate Termination and Route The appliance has a built-in syphonic condensate trap eliminating the need for external traps. Connect to the 22mm plastic drain pipe and extend the pipe run away from the control panel and appliance witha constant fall of 2.5° or 25mm in every metre. See fig. 14. The condensate pipe can terminate into any of four areas: External condensate pipework The syphonic condensate trap collects condensate into a trap which releases it in 100 ml quantities.
Installation Fixing the appliance 3.7 B Fit the washers onto the gas and water connections. Water connections B Lift the boiler onto the wall-mounting frame. The lugs pass through the rectangular holes in the boiler back panel. B Take care not to disturb the washers on the connections. Connecting the flue assembly B Fit flue duct connector onto appliance flue spigot. B Secure with the screws supplied.
Installation 3.8.1 lighting, activated by passive infra-red sensing heads. If the terminal is less than 2 m above a surface to which people have access then a guard must be fitted. The guard must be evenly spaced about the terminal with a space of 50 mm in each direction and fixed with plated screws. A guard Type K6 for the standard horizontal flue, can be obtained from Tower Flue Components, Vale Rise, Tonbridge TN9 1TB.
Installation 3.8.2 Installation of the flue The standard 100 mm diameter horizontal flue system is suitable for lengths up to 4 m. Flues up to 650 mm do not require an extension duct assembly. Flues between 1600 mm and 4000 mm require extension duct assemblies. NOTE: Flue lengths between 650 mm and 730 mm cannot be accommodated. Refer to fig. 19, 20, 21.
Installation Maximum 1600mm Outer Wall Flue Turret Extension Duct Clamp Terminal Assembly 6 720 610 599 - 00.TD Fig. 20 Flue with one extension Outer Wall Flue Turret Clamp Extension Duct Clamp Extension Duct Clamp Terminal Assembly 6 720 610 599 - 01.TD Fig. 21 Flue with extensions Flue Turret Clamp Flue Terminal Extension Flue Duct Wall Sealing Gasket 6 720 610 599 - 01.TD Fig. 22 Flue components 3.8.3 Flue duct preparation and assembly Measure the flue length L. Refer to fig.
Installation The assembly will be made easier if a solvent free grease is lightly applied i.e Silicone lubricant, to the male end of the ducts. L NOTE: An inner wall sealing plate is provided which should be fitted to the ducts before assembly. Push the assembly through the wall and fix the turret to the appliance using the screws provided. Refer to fig. 26. 120 6 720 610 599 - 01.TD Flue Turret Fig.
Electrical connections 4 Electrical connections B Always disconnect the power supply to the appliance at the mains before carrying out any work on the electrical systems and components. B Pull out cover panel at the bottom and remove. Refer to fig. 27. 3 0 4 2 5 1 E All control and safety systems are built into the appliance. B Allow mains cable to protrude at least 50 cm from wall.
Electrical connections B Secure cable in cable grommet by means of cable grip. L N NS 4.2 Wiring to your system The boiler is fitted with an internal pump and there are two recommended ways of connecting a system, external 230v or internal 24v depending on the choice of diverter valve(s). 4.2.1 External 230v Non-supplied parts required: external 230v conventional terminal block or wiring centre, pre-wired to the 230v diverter valve(s) and all other 230v system components.
Commissioning 4.2.2 Internal 24v Non-supplied Worcester Bosch parts required: • See section 4.1 to gain access to the boiler mains wiring centre Description Part Number • Keep the link connecting the Ls and Lr terminals 24v Diverter valve (including tank NTC) 7 719 002 090 • Refer to instructions supplied with each part TR2 room thermostat 7 774 901 137 • Externally wired frost protection is not required as this is provided by the boiler’s internal frost thermostat and the TR2 room thermostat.
Commissioning 5.1 Commissioning Never run the appliance when empty or unpressurised. i The operational CO2 level is set at the factory and no adjustment is necessary when installing a natural gas fired appliance. Benchmark Water Treatment: For optimum performance after installation, this boiler and its associated central heating system should be flushed in accordance with the guidelines given in BS 7593:1992 - Treatment of water in domestic hot water systems.
Commissioning – Central heating systems for flow temperatures up to 88 °C: limited “max” setting for low-temperature operation (see page 27). When the burner is alight, the red indicator lamp lights up. 6 720 610 333-05.1O Fig. 34 5.4 System controls B Set room thermostat to the desired room temperature. B Set room temperature controller, if fitted. Refer to the instructions with the control. B Set the thermostatic radiator valves to the desired settings. 6 720 611 443 GB (03.
Commissioning 5.5 Appliances with optional plug-in diverter valve: Setting hot water temperature B Do not set the temperature higher than 60°C for normal operation. B Only use temperatures of up to 70°C temporarily for thermal disinfection purposes. B Set the hot water temperature by means of the temperature control on the appliance. 5.6 The appliance has an in-built frost protection device which is generally suitable for most applications. B Leave master switch switched on.
Individual settings 6 Individual settings 6.1 Mechanical settings 6.1.1 Checking the size of the expansion vessel Maximum pressure at maximum CH flow temperature is 2.5 bar. If the pressure is greater than this then fit an extra expansion vessel. Refer to table 12. System Capacity – BS 7074:1 Expansion Vessel Pressure and System Capacity Expansion Vessel litres 10 Expansion Vessel Charge Pressure bar 0.
Individual settings 6.2 Settings on the Bosch Heatronic Entering a setting 6.2.1 Operating the Bosch Heatronic B To enter the setting for a function, turn the temperature control . The Bosch Heatronic enables easy setting and checking of a large number of appliance functions. Storing a setting This description is limited to those functions required for commissioning. B Level 1: press and hold the play shows [ ].
Individual settings 6.2.5 i Setting the switching difference (Service Function 2.6) If the appliance is connected to an outside-temperature controlled programmer, the programmer sets the switching difference. It does not need to be set on the appliance. The switching difference is the permissible divergence from the specified CH flow temperature. It can be set in increments of 1°C. The adjustment range is 1 to 30°C (is factory set to 0°C). The minimum CH flow temperature is 30°C. 6.2.
Converting the appliance to different gas types 7 Converting the appliance to different gas types The setting is factory sealed at maximum. Adjustment to the rated heat input and min. heat input is not necessary. Checking the gas supply pressure B Check the gas supply pressure at the gas supply pressure testing point. i Natural gas appliances must not be operated if the gas supply pressure is below 18 mbar or above 24 mbar.
Converting the appliance to different gas types B Turn the temperature control until the display shows 2. (= max. rated heat output). The display and the button will flash. B Remove the seal from the gas valve adjusting screw (64) and adjust the CO2 level to the figure given in Table 15 for min. rated heat output. 64 6 720 610 332-61.1O Fig. 45 B Measure the CO2 level. B Prise off the seal on the gas flow restrictor. B Adjust the gas flow restrictor (63) to obtain the CO2 level given in Table 15.
Converting the appliance to different gas types 7.2 Testing combustion air/flue gas at set heat output 7.2.1 Testing the O2 or CO2 level in the combustion air i By testing the O 2 or CO2 level in the combustion air the gas tightness of a type C 13 or C33 flue system can be checked. The O2 level must not be less than 20,6 %. The CO2 level must not exceed 0,2 %. B Press and hold the button until the display shows – –. “Chimney sweep” mode is now active.
Maintenance 8 Maintenance B Always disconnect the appliance from the electrical power supply (fuse, circuit breaker) before carrying out any work on the electrical systems or components. B Always turn off the gas cock before carrying out any work on components which carry gas. i There is a special Service booklet for the Engineer, order no. 7-181-465-346, available to competent persons. i All safety and control systems are monitored by the Bosch Heatronic.
Maintenance 8.1 Pre-Service Check List Date 1 Call up the last fault stored by the Bosch Heatronic, Service Function .0, (see page 35). 2 Check ionisation current, Service Function 3.3, (see page 35). 3 Perform visual check of air/flue duct.Visual check of diaphragm for soiling and splits (see page 37). 4 Check gas supply pressure (see page 30). 5 Test combustion air/flue gas (see page 32). 6 Check CO 2 setting for min./ max. (gas/air ratio) (see page 30). mbar min. % max.
Maintenance 8.2 Description of servicing operations The combustion performance must be checked before and after any servicing work on the combustion and burner components. Refer to section 7.1. B Remove the fan and the burner as described in the text headed “Burner” (see page 36). Check “Last fault stored”: B Select Service Function .0 (see page 28 “Selecting service function”). There is a list of the fault codes in the Appendix (see page 42).
Maintenance B Clean out the condensate collector and trap connection (with other end of brush). 6 720 610 332-75.2R Fig. 54 B Refit the clean-out cover using a new seal and tighten screws to torque of approx. 5 Nm. Burner B Check that the gas cock is turned off and the master switch is in the OFF position. B Remove the clips (1.) and unscrew the two bolts (2.). Refer to fig. 55. B Unscrew and remove the two hexagon screws securing the fan (3.). 7 181 465 330-09.2R Fig.
Maintenance Siphon Diaphragm in mixer unit B Take care not to damage diaphragm (443) when removing and refitting it. B Unscrew the clip and disconnect the pipe to the siphon. B Remove the drain plug to drain the siphon. B Open mixer unit (29). B Carefully withdraw diaphragm (443) from fan intake tube and check for soiling and splits. 3. B Unscrew the securing nut from beneath the side facia and remove the siphon. Refer to figure below. B Refit and prime the siphon.
Maintenance 8.3 B Remove the pcb control board. Replacement of Parts Before changing any components check that the gas is turned off and that the appliance is electrically isolated. When necessary close the system valves and drain the appliance. Refitting is a reverse of the procedure for removal using new seals or o-rings as appropriate. 8.3.1 PCB control board and transformer B Switch off the appliance. B Disconnect appliance from the power supply. B Unplug all connectors from the control box (inc.
Maintenance 8.3.2 Fan Assembly 8.3.3 3. Pump B Switch off the appliance. B Disconnect appliance from the power supply. B Remove two switchbox fixing screws (1.). Refer to fig. 62. 2. B Lower switchbox (2.). B Unscrew and remove the siphon by releasing the jubilee clip. Refer to fig. 58. B Unscrew the pump union nuts (3). Refer to fig. 62. 4. B Carefully remove the pump and disconnect the leads.
Maintenance B Remove 3-way valve. 8.3.7 Gas Valve B Check that the gas cock is turned off. B Lower the control panel. Refer to fig. 62. B Pull off the solenoid connections at the rear of the valve. B Undo the union, within the inner casing, securing the valve to the gas/air tube. Refer to fig. 61. B Remove the white plastic cap from the gas valve. B Release the gas inlet union at the manifold assembly.
Maintenance 8.3.9 Pressure gauge B Drain the appliance. B Lower the facia. Refer to fig. 62. B Ensure that all the seals are in place and all of the connections are tight before re-commissioning the appliance. B Twist the pressure gauge head anti-clockwise to release it from the casing. Refer to fig. 2. B Disconnect the capillary head from the rear by withdrawing the clip and pulling out the head. Refer to fig. 57. 8.3.10 Expansion vessel B Drain the appliance.
Appendix 9 Appendix 9.1 Fault Codes More detailed fault finding procedures are described in the Service booklet for the Engineer number 7 181 465 346. Display code Description Remedy A8 Break in communication Check connecting lead to programmer AC Module not detected. Check connecting lead between TA211E/TR212E and Heatronic b1 Code plug not detected. Insert code plug correctly, test and replace if necessary. C1 Fan speed too low.
Appendix 9.2 Short parts list Key Description Qty GC Spare part number 1 Sensor - Flue gas temp. 1 8 722 963 858 0 2 Sensor - CH flow temp.
Fan speed reduces over 15 secs. Fan min. speed for 90 secs. Boiler unused for long period.* Yes *Minimum heat input for 15min. No Ignition sequence Ignition spark for 5 seconds. Burner lights. Red light ON. Yes CH demand satisfied. Gas valve closes. Red light OFF. Pump and Fan run for up to 3 mins. No 6 720 611 443 GB (03.11) Repeats 5 times (N.G.) or 3 times (L.P.G.) before lock-out. Fan runs to purge gas from burner.
Appendix 6 720 611 443 GB (03.
Appendix 46 6 720 611 443 GB (03.
Appendix 6 720 611 443 GB (03.
Appendix EXCELLENCE COMES AS STANDARD Worcester Bosch, Cotswold Way, Warndon, Worcester WR4 9SW.
